A Low Carb Diet and Weight Loss

Written by Dr. Steve Chaney on . Posted in low carb diet, Weight Loss

Do Low-Carb Diets Help Maintain Weight Loss?

Author: Dr. Stephen Chaney

 

low carb dietTraditional diets have been based on counting calories, but are all calories equal? Low-carb enthusiasts have long claimed that diets high in sugar and refined carbs cause obesity. Their hypothesis is based on the fact that high blood sugar levels cause a spike in insulin levels, and insulin promotes fat storage.

The problem is that there has been scant evidence to support that hypothesis. In fact, a recent meta-analysis of 32 published clinical studies (KD Hall and J Guo, Gastroenterology, 152: 1718-1727, 2017 ) concluded that low-fat diets resulted in a higher metabolic rate and greater fat loss than isocaloric low-carbohydrate diets.

However, low-carb enthusiasts persisted. They argued that the studies included in the meta-analysis were too short to adequately measure the metabolic effects of a low-carb diet. Recently, a study has been published in the British Medical Journal (CB Ebbeling et al, BMJ 2018, 363:k4583 ) that appears to vindicate their position.

Are low carb diets best for long term weight loss?

Low-carb enthusiasts claim the study conclusively shows that low-carb diets are best for losing weight and for keeping it off once you have lost it. They are saying that it is time to shift away from counting calories and from promoting low-fat diets and focus on low-carb diets instead if we wish to solve the obesity epidemic. In this article I will focus on three issues:

  • How good was the study?
  • What were its limitations?
  • Are the claims justified?

 

How Was The Study Designed?

low carb diet studyThe investigators started with 234 overweight adults (30% male, 78% white, average age 40, BMI 32) recruited from the campus of Framingham State University in Massachusetts. All participants were put on a diet that restricted calories to 60% of estimated needs for 10 weeks. The diet consisted of 45% of calories from carbohydrate, 30% from fat, and 25% from protein. [So much for the claim that the study showed low-carb diets were more effective for weight loss. The diet used for the weight loss portion of the diet was not low-carb.]

During the initial phase of the study 161 of the participants achieved 10% weight loss. These participants were randomly divided into 3 groups for the weight maintenance phase of the study.

  • The diet composition of the high-carb group was 60% carbohydrate, 20% fat, and 20% protein.
  • The diet composition of the moderate-carb group was 40% carbohydrate, 40% fat, and 20% protein.
  • The diet composition of the low-carb group was 20% carbohydrate, 60% fat, and 20% protein.

Other important characteristics of the study were:

  • The weight maintenance portion of the study lasted 5 months – much longer than any previous study.
  • All meals were designed by dietitians and prepared by a commercial food service. The meals were either served in a cafeteria or packaged to be taken home by the participants.
  • The caloric content of the meals was individually adjusted on a weekly basis so that weight was kept within a ± 4-pound range during the 5-month maintenance phase.
  • Sugar, saturated fat, and sodium were limited and kept relatively constant among the 3 diets.

120 participants made it through the 5-month maintenance phase.

 

Do Low-Carb Diets Help Maintain Weight Loss?

low carb diet maintain weight lossThe results were striking:

  • The low-carb group burned an additional 278 calories/day compared to the high-carb group and 131 calories/day more than the moderate-carbohydrate group.
  • These differences were even higher for those individuals with higher insulin secretion at the beginning of the maintenance phase of the study.
  • These differences lead the authors to hypothesize that low-carb diets might be more effective for weight maintenance than other diets.

 

What Are The Pros And Cons Of This Study?

low carb diet pros and consThis was a very well-done study. In fact, it is the most ambitious and well-controlled study of its kind. However, like any other clinical study, it has its limitations. It also needs to be repeated.

The pros of the study are obvious. It was a long study and the dietary intake of the participants was tightly controlled.

As for cons, here are the three limitations of the study listed by the authors:

#1: Potential Measurement Error: This section of the paper was a highly technical consideration of the method used to measure energy expenditure. Suffice it to say that the method they used to measure calories burned per day may overestimate calories burned in the low-carb group. That, of course, would invalidate the major findings of the study. It is unlikely, but it is why the study needs to be repeated using a different measure of energy expenditure.

#2: Compliance: Although the participants were provided with all their meals, there was no way of being sure they ate them. There was also no way of knowing whether they may have eaten other foods in addition to the food they were provided. Again, this is unlikely, but cannot be eliminated from consideration.

#3: Generalizability: This is simply an acknowledgement that the greatest strength of this study is also its greatest weakness. The authors acknowledged that their study was conducted in such a tightly controlled manner it is difficult to translate their findings to the real world. For example:

  • Sugar and saturated fat were restricted and were at very similar levels in all 3 diets. In the real world, people consuming a high-carb diet are likely to consume more sugar than people in the other diet groups. Similarly, people consuming the low-carb diet are likely to consume more saturated fat than people in the other diet groups.
  • Weight was kept constant in the weight maintenance phase by constantly adjusting caloric intake. Unfortunately, this seldom happens in the real world. Most people gain weight once they go off their diet – and this is just as true with low-carb diets as with other diets.
  • The participants had access to dietitian-designed prepared meals 3 times a day for 5 months. This almost never happens in the real world. The authors said “…these results [their data] must be reconciled with the long-term weight loss trials relying on nutrition education and behavioral counseling that find only a small advantage for low carbohydrate compared with low fat diets according to several recent meta-analyses.” [I would add that in the real world, people do not even have access to nutritional education and behavioral modification.]

 

low carb diet and youWhat Does This Study Mean For You?

  • This study shows that under very tightly controlled conditions (dietitian-prepared meals, sugar and saturated fat limited to healthy levels, calories continually adjusted so that weight remains constant) a low-carb diet burns more calories per day than a moderate-carb or high-carb diet. These findings show that it is theoretically possible to increase your metabolic weight and successfully maintain a healthy weight on a low-carb diet. These are the headlines you probably saw. However, a careful reading of the study provides a much more nuanced viewpoint. For example, the fact that the study conditions were so tightly controlled makes it difficult to translate these findings to the real world.
  • In fact, the authors of the study acknowledged that multiple clinical studies show this almost never happens in the real world. These studies show that most people regain the weight they have lost on low-carb diets. More importantly, the rate of weight regain is virtually identical on low-carb and low-fat diets. Consequently, the authors of the current study concluded “…translation [of their results to the real world] requires exploration in future mechanistic oriented research.” Simply put, the authors are saying that more research is needed to provide a mechanistic explanation for this discrepancy before one can make recommendations that are relevant to weight loss and weight maintenance in the real world.
  • The authors also discussed the results of their study in light of a recent, well-designed 12-month study (CD Gardener et al, JAMA, 319: 667-669, 2018 ) that showed no difference in weight change between a healthy low-fat versus a healthy low-carbohydrate diet. That study also reported that the results were unaffected by insulin secretion at baseline. The authors of the current study noted that “…[in the previous study] participants were instructed to minimize or eliminate refined grains and added sugars and maximize intake of vegetables. Probably for this reason, the reported glycemic load [effect of the diet on blood sugar levels] of the low-fat diet was very low…and similar to [the low-carb diet].” In short, the authors of the current study were acknowledging that diets which focus on healthy, plant-based carbohydrates and eliminate sugar, refined grains, and processed foods may be as effective as low-carb diets for helping maintain a healthy weight.
  • This would also be consistent with previous studies showing that primarily plant-based, low-carb diets are more effective at maintaining a healthy weight and better health outcomes long-term than the typical American version of the low-fat diet, which is high in sugar and refined grains. In contrast, meat-based, low-carb diets are no more effective than the American version of the low-fat diet at preventing weight gain and poor health outcomes. I have covered these studies in detail in my book “Slaying The Food Myths.”

Consequently, the lead author of the most recent study has said: “The findings [of this study] do not impugn whole fruits, beans and other unprocessed carbohydrates. Rather, the study suggests that reducing foods with added sugar, flour, and other refined carbohydrates could help people maintain weight loss….” This is something we all can agree on, but strangely this is not reflected in the headlines you may have seen in the media.

The Bottom Line

 

  • A recent study compared the calories burned per day on a low-carb, moderate-carb, and high-carb diet. The study concluded that the low-carb diet burned significantly more calories per day than the other two diets and might be suitable for long-term weight control. If confirmed by subsequent studies, this would be the first real evidence that low-carb diets are superior for maintaining a healthy weight.
  • However, the study has some major limitations. For example, it used a methodology that may overestimate the benefits of a low-carb diet, and it was performed under tightly controlled conditions that can never be duplicated in the real world. As acknowledged by the authors, this study is also contradicted by multiple previous studies. Further studies will be required to confirm the results of this study and show how it can be applied in the real world.
  • In addition, the kind of carbohydrate in the diet is every bit as important as the amount of carbohydrate. The authors acknowledge that the differences seen in their study apply mainly to carbohydrates from sugar, refined grains, and processed foods. They advocate diets with low glycemic load (small effects on blood sugar and insulin levels) and acknowledge this can also be achieved by incorporating low-glycemic load, plant-based carbohydrates into your diet. This is something we all can agree on, but strangely this is not reflected in the headlines you may have seen in the media.
  • Finally, clinical studies report averages, but none of us are average. When you examine the data from the current study, it is evident that some participants burned more calories per hour on the high-carb diet than other participants did on the low carb diet. That reinforces the observation that some people lose weight more effectively on low-carb diets while others lose weight more effectively on low-fat diets. If you are someone who does better on a low-carb diet, the best available evidence suggests you will have better long-term health outcomes on a primarily plant-based, low-carb diet such as the low-carb version of the Mediterranean diet.

For more details read the article above.

 

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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Comments (1)

  • Merlena Cushing

    |

    Dr. Chaney, I can’t recall where you listed what you believe to be the most reliable sources of studies (clinical and otherwise.) I do know you value PubMed and JAMA. How about New England Journal of Medicine and others. Thanks.

    Reply

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Latest Article

Groin Pain Relief

Posted April 16, 2019 by Dr. Steve Chaney

What Is The Pectineus Muscle And Why Is It Important?

Author: Julie Donnelly, LMT –The Pain Relief Expert

Editor: Dr. Steve Chaney

 

Spring Is In The Air

spring floridaI remember as a child we sang “Though April showers may come your way…they bring the flowers that bloom in May…”

Of course, here in Florida we are blessed with flowers all year, but there’s still a lovely feeling that happens in Spring.  It’s still cool enough most days to go out running, and the humidity is still low.  Traffic will soon be easing up as our friends from the north start their trek back home, and daylight savings time is giving us more time to get to the beach for sunset.  Lovely!

Fun Facts About Spring….

  • The earliest known use of the term “spring cleaning” was in 1857
  • The word “spring” has been used for the season since the 16th century
  • The first day of spring is called the vernal equinox
  • On the first day of spring, the sunrise and sunset are about 12 hours apart everywhere on earth
  • Spring fever isn’t just a saying. Experts say the body changes due to the temperature and can cause an upset in your health.
  • The actual start of spring varies from March 19th to the 21st, but it is commonly celebrated on the 21st.

Do you like to garden?  Now is the perfect time to get your gardens planted so you’ll have home grown veggies for the entire summer.  For me, it’s also a great time to do some spring cleaning and get the house in order before the summer closes all the windows and the air conditioning becomes our indoor relief.

But these activities can also cause a strain on muscles, so don’t forget to take care of yourself. If you put too much strain on muscles you haven’t used all winter, you can develop problems and need groin pain relief.

 

A Tiny Muscle Can Cause Groin Pain

groin pain relief pectineusLately I’ve had several clients come in because of groin pain that has their medical practitioners stumped.  Their symptoms are varied, but most complain that it feels like they hit their pubic bone with a rubber mallet.  Ouch!

One client loves to ride her horse, but the pain had prevented that for several weeks. Another was considering selling the motorcycle that she and her husband love because she just can’t sit on it anymore.

Several years ago, I had a male client tell me that he had this same pain and he was told it could be his prostrate causing the issue.  Fortunately, that wasn’t he problem at all.

The muscle that caused all these problems, and a lot more, is the Pectineus.

The Pectineus muscle originates on your pubic bone and inserts into the very top of your inner thigh bone (femur).

You can see the Pectineus and surrounding muscles more clearly by going to https://en.wikipedia.org/wiki/Pectineus_muscle

Most muscles have more than one function, and this is true for the Pectineus.  The function we’ll look at today is called adduction.  It brings your leg in toward midline.  If you think of a soccer player kicking the ball with the inside of his ankle, it was the Pectineus that helped draw his leg in so he could do the shot.

Each of my clients had pain while trying to bring their leg out so they could sit on their horse, or on their motorcycle.  The tight muscle was pulling on their pubic bone and causing a severe strain.

This muscle is easier to have someone else treat it for you because of its location but give it a try and see if you can locate & treat it yourself.

 

Groin Pain Relief

groin pain relief treatmentThe picture to the left is showing an athlete self-treating her adductors.  These muscles, and the Pectineus muscle, all originate at the same point on the pubic bone.  The picture is showing her massaging the middle of the adductors.

To reach the Pectineus, move the ball all the way up to the crease in your leg.  You can do the treatment with a ball, but because of the size of the muscle and its location, it’s easier to do it with your fingertips.

Sit as this athlete is sitting, and even bring your opposite leg up so your foot is flat on the floor.  For example, in this picture, the athlete would bring her right leg up so her right foot is on the floor, and then lean a bit further onto her left hip.  That opens up the area so she can reach a bit easier into the muscle while using her fingertips.

Press into the muscle, being careful to feel for a pulse, and moving if you feel one.  If the Pectineus is in spasm, you’ll know it immediately when you press on it.  If it’s not in spasm, you won’t be able to find it at all.

Remember to stay within your pain tolerance level, this isn’t a “no pain, no gain” situation.  Never go deeper than what feels tender, but not so much that you want to faint. Hold the pressure for 15 seconds. Then let up on the pressure, but keep your fingers in the same place.

Repeat this movement several times. Each time it will hurt less, and eventually it won’t hurt at all.  That’s when the muscle has completely released, and you will have relief from the pain.

It’s as simple as that!

Why stay in pain when it’s so easy to find the muscular source of the problem and eliminate it?

calf cramps remedy bookTreat Yourself to Pain-Free Living (https://julstromethod.com/product/treat-yourself-to-pain-free-living-hardcopy/). It is filled with over 100 pictures and descriptions proven to show you how to find and self-treat muscle spasms from head to foot!

Join the 1000’s of people worldwide who have discovered that tight muscles were the true source of pains they thought were from arthritis, fibromyalgia, and other serious conditions.  You have nothing to lose, and everything to gain by releasing tight muscles.

Treat Yourself to Pain-Free Living is your step-by-step guide to pain relief!

 

Wishing you well,

 

Julie Donnelly

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

 

julie donnellyAbout The Author

Julie Donnelly is a Deep Muscle Massage Therapist with 20 years of experience specializing in the treatment of chronic joint pain and sports injuries. She has worked extensively with elite athletes and patients who have been unsuccessful at finding relief through the more conventional therapies.

She has been widely published, both on – and off – line, in magazines, newsletters, and newspapers around the country. She is also often chosen to speak at national conventions, medical schools, and health facilities nationwide.

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